Ravens RB Ray Rice has "a significant contusion" on his knee, the team said Monday.
Rice left Sunday's win over Cleveland with about 10 minutes remaining after gaining four yards on a pass reception. He had an MRI on Monday, which revealed the contusion, head coach John Harbaugh said Monday. The team declined to reveal which knee Rice had injured.
His status for Sunday's game against undefeated Pittsburgh is unknown.
"We'll see how he fares throughout the week," Harbaugh said. "We'll see how it heals."
If Rice is unable to play against the Steelers, Willis McGahee would be the starting running back.